Additive manufactured part with enhanced rigidity and method of manufacturing the same

ABSTRACT

An additive manufactured part is formed as a solid body of material including additive manufacturing powder, binder material supporting the powder in the shape of the solid body, and strengthening resin infused within the solid body. The additive manufacturing powder can be sand. The infused resin can be a two-part resin wherein an inert gas is added to the mixture of the two parts of the two-part resin during mixing. The infused resin can be infused inwardly from the peripheral surface of the solid body and can penetrate partially or fully through the thickness of the solid body.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationNo. 62/844,142, filed May 7, 2019, and U.S. Provisional PatentApplication No. 62/900,830, filed Sep. 16, 2019, each of which isincorporated by reference herein in its entirety.

BACKGROUND

An additive manufacturing process can form a part by depositing powderin successive layers that together define the shape of the finishedpart. A binder material is deposited with the powder to support andretain the powder in the desired shape. In some instances, sand is usedas the powder.

SUMMARY

An additive manufactured part comprises a solid body of materialincluding additive manufacturing powder, binder material supporting thepowder in the shape of the solid body, and strengthening resin infusedwithin the solid body.

The additive manufacturing powder can be sand. The infused resin can bea two-part resin including an epoxy resin and an epoxy curing agent. Theinfused resin can be infused inwardly from the peripheral surface of thesolid body and can penetrate partially or fully through the thickness ofthe solid body.

In given examples, the solid body is formed in the configuration of atool. In one example, the tool is an axe head. In another example, thetool is a vacuum mold tool having a forming surface and air flowchannels communicating with the forming surface. The mold tool can besupported on rails for sliding across a base in a vacuum mold assembly.Such a mold tool can be one of multiple tools that slide into adjoiningpositions in which they define a combined forming surface. The mold toolcan also have trim lines defined by cuts in the forming surface.

A method of forming the part first forms a porous body of additivemanufacturing powder and binder material. Strengthening resin is theninfused into the porous body and is cured within the porous body.

When used as a mold tool, the part is placed on a base having air flowchannels communicating with the air flow channels in the mold tool. Asheet of vacuum molding material is placed over the forming surface ofthe mold tool. Vacuum pressure is applied in the air flow channels inthe base and the mold tool to draw the sheet of molding material againstthe forming surface.

In one method, an inert gas is introduced into a two-part infusion resinand/or two-part tooling gel coat during mixing of the two partstogether. In one aspect, the inert gas may be nitrogen gas or argon gas.

In one aspect, a method is provided, the method comprising: forming aporous body of additive manufacturing powder and binder material in anadditive manufacturing process; infusing resin into the porous body,wherein the resin is a two-part resin including a resin and a hardener,and wherein an inert gas is applied to the two-part resin during mixtureof the resin and the hardener; and curing the infused resin within theporous body.

In another aspect, a method is provided, the method comprising: placinga mold tool on a base having air flow channels, the mold tool having aforming surface and air flow channels communicating the forming surfacewith the air flow channels in the base; wherein the mold tool comprisesadditive manufacturing powder and a binder supporting the additivemanufacturing powder as a solid body having the forming surface, andfurther comprising a resin infused within the solid body, wherein theresin is a two-part resin including a resin and a hardener, and whereinan inert gas is applied to the two-part resin during mixture of theresin and the hardener; placing a sheet of vacuum molding material overthe forming surface; and applying vacuum pressure in the air flowchannels in the base and the mold tool to draw the sheet of moldingmaterial against the forming surface.

In one aspect, an apparatus is provided, the apparatus comprising: asolid body of material having a shape, wherein the material includesadditive manufacturing powder, binder material supporting the additivemanufacturing powder in the shape of the solid body, and resin infusedwithin the solid body, wherein the resin is a two-part resin including aresin and a hardener, and wherein an inert gas is applied to thetwo-part resin during mixture of the resin and the hardener.

In another aspect, an apparatus is provided, the apparatus comprising: amold tool having a forming surface and air flow channels communicatingwith the forming surface; wherein the mold tool includes additivemanufacturing powder, a binder supporting the additive manufacturingpowder as a solid body having the forming surface, and resin infusedwithin the solid body, wherein the resin is a two-part resin including aresin and a hardener, and wherein an inert gas is applied to thetwo-part resin during mixture of the resin and the hardener.

In one aspect, a mixing tool is provided, the mixing tool comprising: ahousing having a hollow bore; a mixing shaft extending through thehollow bore, wherein the mixing shaft includes a mixing head at a distalend of the mixing shaft, and wherein the mixing shaft includes aproximate end engaged by a rotation-inducing device; and an air linehaving a nozzle at a distal end, wherein the air line contains a flow ofan inert gas directed through the nozzle, and wherein the nozzle isoriented near the mixing head.

In another aspect, an apparatus is provided, the apparatus comprising: amold tool having a forming surface and air flow channels communicatingwith the forming surface; wherein the mold tool includes additivemanufacturing powder, a binder supporting the additive manufacturingpowder as a solid body having the forming surface, and resin infusedwithin the solid body, wherein the resin is a two-part resin including aresin and a hardener, and wherein an inert gas is applied to thetwo-part resin during mixture of the resin and the hardener; and whereinthe mold tool includes an ejector element extending through the formingsurface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flow chart of steps taken in a method of forming an additivemanufactured part.

FIG. 2 also is a flow chart of steps taken in a method of forming anadditive manufactured part.

FIG. 3 is another flow chart of steps taken in a method of forming anadditive manufactured part.

FIG. 4A is a view of a partially formed additive manufactured part.

FIG. 4B is a view of an additive manufactured part.

FIG. 5A is a partial sectional view of an additive manufactured part.

FIG. 5B is a view similar to FIG. 5A showing an alternative structure ofthe part.

FIG. 6A is a view of an additive manufactured part configured as avacuum mold tool.

FIG. 6B is a view of an additive manufactured part configured as avacuum mold tool.

FIG. 6C is a view of an additive manufactured part configured as avacuum mold tool.

FIG. 6D is a view of an additive manufactured part configured as avacuum mold tool.

FIG. 7A is a view of an additive manufactured part with rails for use ofthe part as a vacuum mold tool.

FIG. 7B is a view showing the apparatus of FIG. 7A on a base in a vacuummold assembly.

FIG. 8 is a bottom view of an additive manufactured part configured as avacuum mold tool.

FIG. 9 is a schematic side sectional view of a base in a vacuum moldassembly.

FIG. 10 is a schematic side sectional view showing a vacuum mold tool onthe base of FIG. 9.

FIG. 11 is a view of another additive manufactured part configured as avacuum mold tool.

FIG. 12 is a view of another additive manufactured part configured as avacuum mold tool.

FIG. 13A illustrates a pair of additive manufactured parts configured asvacuum mold tools, also showing parts of a vacuum mold assembly.

FIG. 13B illustrates a pair of additive manufactured parts configured asvacuum mold tools, also showing parts of a vacuum mold assembly.

FIG. 13C illustrates a pair of additive manufactured parts configured asvacuum mold tools, also showing parts of a vacuum mold assembly.

FIG. 14A is a view of an additive manufactured part with rails for useof the part as a vacuum mold tool.

FIG. 14B is a sectional view of an additive manufactured part with railsfor use of the part as a vacuum mold tool.

FIG. 14C is a view of an additive manufactured part with rails for useof the part as a vacuum mold tool.

FIG. 14D is a view of an additive manufactured part with rails for useof the part as a vacuum mold tool.

FIG. 14E is a view of a pair of additive manufactured parts with railsfor use of the part as a vacuum mold tool.

FIG. 14F is a view of a pair of additive manufactured parts with railsfor use of the part as a vacuum mold tool.

FIG. 15A is a sectional view of an additive manufactured part with arail for use of the part as a vacuum mold tool.

FIG. 15B is a partial sectional view of the additive manufactured partillustrated in FIG. 15A.

FIG. 16 is a view of an additive manufactured part with rails for use ofthe part as a vacuum mold tool.

FIG. 17A is a view of tool for mixing a two-part resin and/or coatingwhile introducing an inert gas into the mixture.

FIG. 17B is a view of tool for mixing a two-part resin and/or coatingwhile introducing an inert gas into the mixture.

FIG. 17C is a sectional view of tool for mixing a two-part resin and/orcoating while introducing an inert gas into the mixture.

FIG. 18 is a flow chart of steps taken in a method of forming anadditive manufactured part.

FIG. 19 is a side sectional view showing a vacuum mold tool with apneumatic ejector element.

FIG. 20A is a view of a pneumatic ejector element.

FIG. 20B is a view of a pneumatic ejector element.

FIG. 21A is a sectional view of a pneumatic ejector element in aretraced position.

FIG. 21B is a sectional view of a pneumatic ejector element in anextended position.

DETAILED DESCRIPTION

The apparatus illustrated in the drawings includes structures that areexamples of the elements recited in the apparatus claims and can beemployed to perform the steps recited in the method claims. Theillustrated apparatus thus includes examples of how a person of ordinaryskill in the art can make and use the claimed invention. These examplesare described to meet the written description and enablementrequirements of the patent statute without imposing limitations that arenot recited in the claims. One or more elements of one aspect may beused in combination with, or as a substitute for, one or more elementsof another aspect as needed for any particular implementation of theclaimed invention.

As shown in FIGS. 1, 2, and 3, methods of forming and using an additivemanufactured part can be performed in the steps summarized.

Method 100 may include the following steps: create part from a sand andbinder mixture using additive manufacturing (102) and infuse sand andbinder part with resin penetrating into the surface of the sand andbinder part (104).

Method 200 may include the following steps: create part from a sand andbinder mixture using additive manufacturing, the part including squareapertures for guide rails and channel holes for uniform vacuumapplication (202); infuse sand and binder part with resin penetratinginto the surface of the sand and binder part (204); polish the formingsurface of the part to a desired surface finish (206); add trim lines tothe forming surface of the part (208); attach part to a base, the baseincluding vacuum holes and channels for application of a vacuum (210);apply sheet of heated material to be molded to the forming surface ofthe part (212); and apply a vacuum to the part, creating a negativepressure within the vacuum holes and channels in the base, and channelholes within the part (214).

Method 300 may include the following steps: create part from a sand andbinder mixture using additive manufacturing, the part including squareapertures for guide rails and channel holes for uniform vacuumapplication (302); infuse sand and binder part with resin penetratinginto the surface of the sand and binder part (304); polish the formingsurface of the part to a desired surface finish (306); add trim lines tothe forming surface of the part (308); attach part to additional partsformed in the same manner, creating a multi-part forming surface (310);attach parts to a base, the base including vacuum holes and channels forapplication of a vacuum (312); apply sheet of heated material to bemolded to the multi-part forming surface (314); and apply a vacuum tothe parts, creating a negative pressure within the vacuum holes andchannels in the base, and channel holes within the part (316).

FIG. 4 is a partial view of a porous body of material 400. The porousbody 400 has the shape of a tool, specifically the axe head 402 of FIG.4B. The material of which the body 400 is formed includes additivemanufacturing powder, and further includes binder material that is curedto support the powder in the shape of the body 400. The additivemanufacturing powder in this example is sand. The binder material can beany suitable binder material known in the art.

In the condition shown in FIG. 4A, the body 400 includes only the sandand the cured binder that holds the sand in the shape of the axe head.The body 400 may thus be referred to as “green.” However, in thecondition of FIG. 4B, a resin 404 has been infused into the porousstructure of the body 400. The infused resin 404 overlies the peripheralsurface 406 (FIG. 4A) of the body 400 and penetrates inwardly from theperipheral surface 406. The resin 404 can be applied manually at theperipheral surface 406, and the penetration may be accomplished bywicking action in the porous structure of the body 400. When cured, theinfused resin 404 imparts additional rigidity so that the body 400 as awhole can serve as an axe head 402, whereas a green sand/binder materialalone would not have the rigidity needed for an axe head. A resinmaterial including both an epoxy resin and an epoxy curing agent may bepreferable.

Another example of an additive manufactured part 500 is shown partiallyin the cross-sectional view of FIG. 5A. The illustrated section 502 ofthe part 500 has a thickness T between opposed peripheral surfaceportions 504 and 506. A resin 510 is infused inwardly from one of theopposed surface portions 504, and penetrates the green sand/bindermaterial 512 to a depth D that is less that the thickness T. The infusedresin 510 could alternatively penetrate through the entire thickness Tor, as shown in the example of FIG. 5B, could be infused inwardly fromboth of the opposed surface portions 504 and 506. The depth ofpenetration can be selected to provide a corresponding degree ofenhanced rigidity as needed for the intended use of the finished part500.

The example of FIGS. 6A-6D is an additive manufactured part configuredfor use as vacuum mold tool. The tool 600 has a contoured formingsurface 602 with vacuum ports 603. The vacuum ports 603 communicate withinternal air flow passages leading to a source of vacuum pressure. Theforming surface 602 is contoured to impart a corresponding contour to asheet of vacuum molding material that is drawn against the formingsurface 602 by the vacuum pressure at the ports 603.

The material of which the tool 600 is formed includes additivemanufacturing powder, which in this example is sand, and furtherincludes binder material that is cured to support the powder in theshape of a vacuum mold tool. Additionally, resin 610 is infused inwardlyfrom the peripheral surface of the sand/binder material. The infusedresin 610 provides the body of sand/binder material with the rigidityneeded for use of the tool 600 as a vacuum mold tool. As describedabove, the infused resin 610 can include an epoxy resin and an epoxycuring agent. Tool 600 may include a lower portion 608 opposite formingsurface 602. Lower portion 608 may interact with and/or engage a base.Side portions 612 may be oriented between forming surface 602 and lowerportion 608. At least a portion of side portions 612 may or may not bepart of the forming surface depending upon the design of tool 600 andwhether a vacuum molding material is intended to contact side portions612.

As further shown in FIGS. 6A-6D, the tool 600 has passages 620 forreceiving rails that support the part 600 on a base in a vacuum moldingassembly. Such a base has air flow passages and ports for communicatingthe vacuum source with the ports 603 and passages in the tool 600. Alsoshown are cut-outs 622 at a bottom side of the tool 600 opposite theforming surface 602. The cut-outs 622 reduce the material and hence theweight of the tool 600, and ribs 624 are provided for strength. Air flowchannels 627 with ports 629 are arranged to communicate with the airflow features of the vacuum molding base; ports 629 may be in fluidcommunication with ports 603.

The example of FIGS. 7A and 7B includes a vacuum mold tool 700 that issubstantially the same as the tool 600 of FIGS. 6A-6D. The tool 700 thushas a contoured forming surface 702 with vacuum ports 703. The vacuumports 703 communicate with internal air flow passages leading to asource of vacuum pressure. The forming surface 702 is contoured toimpart a corresponding contour to a sheet of vacuum molding materialthat is drawn against the forming surface 702 by the vacuum pressure atthe ports 703. The tool 700 likewise has a bottom side with cut-outs,air flow channels, and ports as described with reference to the tool600.

The material of which the tool 700 is formed includes additivemanufacturing powder, which in this example is sand, and furtherincludes binder material that is cured to support the powder in theshape of a vacuum mold tool. Resin 710 is infused inwardly from theperipheral surface of the sand/binder material. The infused resin 710provides the body of sand/binder material with the rigidity needed forthe tool 700 to serve as a vacuum mold tool. The infused resin 710 caninclude an epoxy resin and an epoxy curing agent.

Also shown in FIGS. 7A and 7B are rails 714 reaching through passages720 in the tool 700. The rails 714 support the tool 700 on a vacuumforming base 726 (FIG. 7B). The base 726, which can be formed of wood,or any material capable of being machined and supporting the weight oftool 700, is configured with air flow features as described above.Fasteners 724 support the rails 714 on the base 726 such that the tool700 can slide along the rails 714 for alignment with the air flowfeatures in the base 726. The fasteners 714 also bear a substantialportion of the weight of the tool 700.

FIG. 8 is a bottom view of a tool 800 that differs from the tool 700 byhaving a differently configured array of cut-outs 822, ribs 824, and airflow channels 827 at the bottom side 808. The air flow channels 827include notches 829 in the ribs 824.

Another example of a vacuum forming base 900 is shown in FIG. 9. Thisbase 900 includes upper and lower panels 902 and 904, each of which canbe formed of wood or any material capable of being machined andsupporting the weight of tool 1000 (FIG. 10). The upper panel 902 has anupper side surface 906 with a planar contour for supporting an additivemanufactured vacuum mold tool as described above. The lower panel 904has a lower side surface 908 with a central port 909. A fitting 910 isprovided to connect the port 909 with a vacuum air line. An array ofpassages 913 between the panels 902 and 904 communicate the port 909with additional passages 915 that reach through the upper panel 902 tovacuum ports 917 at the upper side surface 906. A peripheral seal 920 isprovided between the panels 902 and 904.

As shown in FIG. 10, another example of an additive manufactured vacuummold tool 1000 is shown in an operative position on the base 900 of FIG.9. Like the mold tools described above, this tool 1000 is formed ofmaterial including additive manufacturing powder, preferably sand, andbinder material that is cured to support the powder in the shape of avacuum mold tool. Resin is infused inwardly from the peripheral surfaceof the body of sand/binder material. The infused resin provides the bodyof sand/binder material with the rigidity needed for the tool 1000 to beused as a vacuum mold tool. The infused resin can include an epoxy resinand an epoxy curing agent.

The tool 1000 has a bottom side 1004 with air flow channels 1007positioned over the vacuum ports 917 at the upper side surface 906 ofthe base 900. Internal air flow passages 1009 in the tool 1000communicate the channels 1007 with vacuum ports 1013 at the formingsurface 1014 of the tool 1000. In use, a heated sheet 1020 of vacuumforming material is placed over the tool 1000 as shown in FIG. 10.Vacuum pressure is then applied through the interconnected channels 913,1007, 1009 and ports 909, 917, 1013 to draw the sheet 1020 against theforming surface 1014, and thereby to form the sheet 1020 with a contourcorresponding to the contour of the forming surface 1014.

In the example of FIG. 11, an additive manufactured vacuum mold tool1100 is provided with trim lines 1102 at the forming surface 1104. Thetrim lines 1102 traverse the outline of a molded part to be cut from asheet of vacuum forming material that has been formed against theforming surface 1104 in the manner described above with reference toFIG. 10. Such trim lines 1102 can be defined by cutting into the formingsurface 1104.

The example of FIG. 12 also shows an additive manufactured mold tool1200 with trim lines 1202 cut into the forming surface 1204. The tool1200 further has additional layers of strengthening resin applied overthe infused strengthening resin to provide a topcoat at the formingsurface 1204. The additional layers of resin may can be applied manuallyand can be sanded and/or polished.

FIGS. 13A-13C show a pair of additive manufactured vacuum mold tools1300 and 1302 with forming surface 1304 and 1306. The forming surface1304 and 1306 are configured to define a combined forming surface 1308when the two mold tools 1300 and 1302 are located in adjoining positionson a base 1310, as shown in FIG. 13C. The mold tools 1300 and 1302 aremoved into the adjoining positions by sliding the tools 1300 and 1302along rails 1312 like the rails 714 described above with reference toFIG. 7.

FIGS. 14A-14F illustrate an additive manufactured part with rails foruse of the part as a vacuum mold tool. The mold tool 1400 may include aforming surface 1404 configured for forming a sheet of vacuum formingmaterial. The mold tool 1400 may include rails 1412 extending throughpassages 1420 extending through the tool 1400. The passages 1420 may beoriented near the bottom 1408 of the tool 1400.

The rails 1412 may be configured to support, handle, and/or index thetools 1400. For support and handling purposes, the length of the rails1412 may be such to allow the rails 1412 to extend completely throughthe tool 1400 and terminate about 8 in.-10 in. (20.3 cm-25.4 cm) out oneor both sides of the tool 1400. Each of the rails 1412 may be spacedapart from adjacent rails 1412 about 12 in.-24 in. (30.5 cm-61.0 cm).

Each of the rails 1412 may be made from any of a variety of materials,with any of a variety of dimensions, capable of handling and supportingthe weight of the tool 1400. For example, the rails 1412 may be madefrom a metal material, a wood material, or the like, and may have adiameter or width of about 1 in.-2 in. (2.5 cm-5.0 cm).

As illustrated in FIGS. 14C and 14D, the rails 1412 may be used tosupport the tool 1400 on a support device 1430, such as an open-endtable, rack, or the like. As illustrated in FIG. 14D, the tool 1400 maybe inverted, using the rails 1412 to both handle and support the tool1400. In this manner, all areas along the periphery of the tool 1400 maybe accessed for processing in preparing and finishing the tool.

As illustrated in FIGS. 14E and 14F, the rails 1412 may be used to indexa plurality of tools 1400, 1402 adjacent to one another for the formingof multiple vacuum form parts at one, or to assemble multiple parts of amodular, larger tool. The first tool 1400 may have a first formingsurface 1404, while the second tool 1402 may have a second formingsurface 1406. Optionally, the first and second forming surfaces 1404,1406 may be sections of a larger forming surface. The first tool 1400and the second tool 1402 may slide along the rails 1412 into a desiredorientation relative to one another.

FIG. 15A illustrates a sectional view of a mold tool 1500 including arail 1512 extending through a passage 1520. A fastener 1532 may extendthrough the bottom 1508 of the tool 1500 to secure the tool 1500 to therail 1512. That is, the fastener 1532 may prevent the rail 1512 fromsliding axially in and out of the tool 1500. The fastener 1532 mayinclude any of a variety of fasteners, including a screw. FIG. 15Billustrates a partial sectional view of the tool 1500 illustrated inFIG. 15A, including the fastener 1532 securing the rail 1512 and thetool 1500 to one another.

FIG. 16 illustrates a mold tool 1600 including a forming surface 1604.The tool 1600 may include a plurality of rails 1612 extending throughpassages 1620. Once the tool 1600 no longer needs to be handled,supported, or index with other tools 1600, the rails 1612 may be trimmedapproximately flush to the side of the tool 1600 to avoid getting in theway of use of the tool 1600.

FIGS. 17A-17C illustrate a mixing tool 1700 a two-part resin and/orcoating while introducing an inert gas into the mixture.

Mixing tool 1700 may include a housing 1750. Housing 1750 may include ahandle 1752 configured to be grasped by a user's hand for manipulationof the mixing tool 1700.

The housing 1750 may include a hollow bore, and within the hollow boreof the housing 1750 may extend a mixing shaft 1754. The mixing shaft1754 may be rotatably attached to the housing 1750, for example, via oneor more ball bearing. The mixing shaft 1754 is configured to rotateindependently of the housing 1750. The distal end of the mixing shaft1754 may include a mixing head 1756. The mixing head 1756 may be any ofa variety of devices configured to mix elements, including for example,the two parts (e.g., a resin and a hardener) of a two-part resin and/ortwo-part coating.

The mixing tool 1700 may include a rotation-inducing device 1758. Therotation-inducing device 1758 is capable of rotating the mixing shaft1754 and the mixing head 1756 connected to the distal end of the mixingshaft 1754. The rotation-inducing device 1758 may engage the proximateend of the mixing shaft 1754.

The mixing tool 1700 may include an air line 1760. The air line 1760 maybe a flexible tube configured to introduce an inert gas to a mixture,including for example to the mixture of the two parts (e.g., a resin anda hardener) of a two-part resin and/or two-part coating. During mixingof the two parts by the mixing head 1756, a user of the mixing tool 1700may cause an inert gas to flow through the air line 1760 and out of anozzle 1762 attached to the distal end of the air line. The inert gasmay be one or both of nitrogen and argon. The nozzle 1762 may beoriented to direct the inert gas toward the mixing head 1756, such thatthe inert gas is introduced directly to the site of mixing of theelements. Alternatively, the nozzle 1762 may be oriented to direct theinert gas just below the mixing head 1756, such that the inert gas isintroduced below the site of the mixing and bubbles up through the siteof the mixing of the elements.

The introduction of an inert gas during mixing may increase the glasstransition, or Tg, of the two-part resin and/or two-part coating. Theintroduction of an inert gas during mixing may increase the Tg of thetwo-part resin and/or two-part coating by up to 30% of themanufacturer's stated Tg of the resin and/or coating. The increase ofthe Tg may be as a result of the introduction of the inert gas creatinga mixing cyclone effect that helps to uniformly mix the two parts (e.g.,a resin and a hardener) of the two-part resin and/or coating to achievethe maximum Tg potential in those materials.

The introduction of an inert gas may be included in any of theaforementioned methods of making a mold tool, including for examplemethods 100, 200, 300. In practice, a part formed from a powder (such assand) and binder mixture is infused with a resin, which penetrates intothe surface of the part. The resin may be a two-part resin that is mixedwhile an inert gas is applied to the resin as described above. Oncemixed, the resin is applied to the sand and binder part on a first side(e.g., top) of the part. The resin is allowed to cure for a period oftime (e.g., 24 hours), after which the part may be inverted and resinmay be applied to the sand and binder part on a second side (e.g.,bottom) of the part. The resin is allowed to cure for a period of time(e.g., 24 hours). At this point, the part is approximately as hard ascement.

A surface treatment, such as a two-part coating, may be applied to thepart following application and curing of the resin. The two-part coatingmay be a tooling gel coating. The two-part coating may be mixed while aninert gas is introduced to the mixture as described above. The coatingmay be applied to the part (where the part is a mold tool, the coatingmay be applied to the forming surface). The coating is allowed to curefor a period of time (e.g., 24 hours), and the process is complete.Optionally, one may apply a fine particle, such as sand blastingmaterial, to the coating after it is applied but before it is cured. Theaddition of the fine particle adds a texture to the final tool surface.

FIG. 18 is a flow chart of steps taken in a method 1800 of forming anadditive manufactured part. Method 1800 may include the following steps:create part from a sand and binder mixture using additive manufacturing(1802); infuse sand and binder part with a two-part resin, wherein thetwo parts are mixed while an inert gas (nitrogen and/or argon) isintroduced to the mixture, the resin penetrating into the surface of thesand and binder part (1804); and apply a two-part coating to theresin-infused part, wherein the two parts are mixed while an inert gas(nitrogen and/or argon) is introduced to the mixture, the coatingcovering at least the forming surface of the part (1806).

FIG. 19 is a side sectional view showing a vacuum mold tool 1900 with apneumatic ejector element 1970. The mold tool 1900 may include a formingsurface 1904 and a plurality of rails 1912 extending through passages1920.

The ejector element 1970 may extend through the forming surface 1904.That is, the forming surface 1904 may include an aperture through whichthe ejector element 1970 may extend. As illustrated in FIG. 19, theejector element 1970 may be approximately flush with the forming surface1904 surrounding it while the ejector element 1970 is in its retractedposition. An air line 1972 may extend from the underside of the ejectorelement 1970. The air line 1972 may be fluidically connected to andextend from the ejector element 1970 at the forming surface 1904, to thebottom 1908 of the tool 1900. The air line 1972 may be configured tosupply pressurized air to the ejector element 1970. The air line 1972may include an air fitting 1974 extending from or near the bottom 1908and configured to attach a pressurized air source such as another airline extending from an air compressor. The operation of the ejectorelement 1970 is described further below in reference to FIGS. 21A and21B.

FIG. 20A illustrates a pneumatic ejector element 2070, connected to anair line 2072, which in turn is connected to an air fitting 2074. Thisarrangement is substantially similar to that illustrated in FIG. 19, andmay be arranged within a mold tool such that the ejector element 2070extends approximately flush with a forming surface, the air fitting 2074extends to an outer side/surface of the tool (e.g., the bottom of thetool), and the air line 2072 extends between the air fitting 2074 andthe ejector element 2070. In practice, pressurized air (e.g., from anair compressor) may be selectively supplied to the air fitting 2074,causing it to flow through the air line 2072, and into the pneumaticejector element 2070.

FIG. 20B illustrates an exploded view of the pneumatic ejector element2070. The ejector element 2070 may comprise a poppet 2076, a bushing2078, and an air fitting 2080. The air fitting 2080 may be configured toengage the air line 2072, or alternatively where the mold tool has athickness that is small enough to avoid the need of the air line 2072altogether, the air fitting 2080 may connect directly to a pressurizedair source.

The bushing 2078 may be substantially cylindrical in shape, with anouter diameter configured to fit within an aperture in the mold toolthat is formed at the forming surface. The poppet 2076 may be sized andshaped to fit within the bushing 2078 and may include a biasing element(not shown) to maintain the poppet 2076 in a position within the bushing2078. The operation of the ejector element 2070 is further describedbelow.

FIG. 21A illustrates the ejector element 2170 used in situ in a moldtool 2100. The tool 2100 includes a forming surface 2104. Within anaperture opening into the forming surface 2104, the ejector element 2170is oriented such that its upper surface is approximately flush with theforming surface 2104 when the ejector element 2170 is in a retractedposition. A vacuum formed material 2190 is oriented within the tool 2100in contact with the forming surface 2104.

The ejector element 2170 may include a poppet 2176, a bushing 2178, andan air fitting 2180. The vacuum formed material 2190 may be orientedwithin the tool 2100 so as to contact at least one of the poppet 2176(in its retracted position) and/or the bushing 2178. The bushing 2178may fit within the aperture opening into the forming surface 2104. Theejector element 2170 may include a biasing device 2182 biasing thepoppet 2176 into a retracted position (the retracted position being downand into the ejector element 2170). The biasing device 2182 may be anybiasing device, and for example, may be a coil spring.

The ejector element 2170 illustrated in FIG. 21A is in an “off” andretracted position. This retracted position is the default position ofthe ejector element 2170 when no pressurized air is applied through theair fitting 2180. FIG. 21B illustrates the ejector element 2170 in an“on” and extended position, wherein the poppet 2176 is in an extendedposition (the extended position being up and away from the rest of theejector element 2170.

In practice, the ejector element 2170 is in an “off” position duringvacuum forming of the vacuum formed material 2190. Due to the importanceof the ejector element 2170 not leaking during the vacuum process, thepoppet 2176 and the bushing 2178 may form an air-tight seal against airpressure at the forming surface 2104 when the poppet 2176 is in aretracted position. Upon completion of the vacuum forming process,wherein the vacuum formed material 2190 is ready for removal from thetool 2100, the ejector element 2170 is moved to an “on” position toassist in breaking any adhesive forces between the vacuum formedmaterial 2190 and the forming surface 2104.

When the ejector element 2170 receives a supply of pressurized air 2184at an adequate pressure and flow rate, the poppet 2176 overcomes thebiasing device 2182 to move into an extended position. In the extendedposition, the poppet 2176 engages the vacuum formed material 2190 andpushes the vacuum formed material 2190 away from the forming surface2104. In addition to the physical ramming force supplied to the vacuumformed material 2190 by the poppet 2176, the pressurized air 2184 mayflow through the ejector element 2170 and between the vacuum formedmaterial 2190 and the forming surface 2104. This flow of the pressurizedair 2184 may act to further separate and disengage the vacuum formedmaterial 2190 from the forming surface 2104, thus easing the removal ofthe vacuum formed material 2190 from the tool 2100. The pressure andvolume flow rate of the pressurized air 2184 may be adjusted dependingupon the size, shape complexity, and adhesive forces with the formingsurface 2104 of the vacuum formed material 2190, so as to effect theremoval of the vacuum formed material 2190 without damaging the vacuumformed material 2190.

While only a single ejector element is illustrated within the mold tool,it is contemplated that a plurality of ejector elements may be appliedto any giving tool to assist in the removal of vacuum formed materialsfrom the tool.

While the various examples above recited the use of a pressurized airfor use with the ejector element, it is contemplated that a pressurizedfluid of any variety may be used instead of or in addition to, air.

To the extent that the term “includes” or “including” is used in thespecification or the claims, it is intended to be inclusive in a mannersimilar to the term “comprising” as that term is interpreted whenemployed as a transitional word in a claim. Furthermore, to the extentthat the term “or” is employed (e.g., A or B) it is intended to mean “Aor B or both.” When the applicants intend to indicate “only A or B butnot both” then the term “only A or B but not both” will be employed.Thus, use of the term “or” herein is the inclusive, and not theexclusive use. See Bryan A. Garner, A Dictionary of Modern Legal Usage624 (2d. Ed. 1995). Also, to the extent that the terms “in” or “into”are used in the specification or the claims, it is intended toadditionally mean “on” or “onto.” To the extent that the term“substantially” is used in the specification or the claims, it isintended to take into consideration the degree of precision available inmanufacturing. To the extent that the term “selectively” is used in thespecification or the claims, it is intended to refer to a condition of acomponent wherein a user of the apparatus may activate or deactivate thefeature or function of the component as is necessary or desired in useof the apparatus. To the extent that the term “operatively connected” isused in the specification or the claims, it is intended to mean that theidentified components are connected in a way to perform a designatedfunction. As used in the specification and the claims, the singularforms “a,” “an,” and “the” include the plural. Finally, where the term“about” is used in conjunction with a number, it is intended to include±10% of the number. In other words, “about 10” may mean from 9 to 11.

As stated above, while the present application has been illustrated bythe description of aspects thereof, and while the aspects have beendescribed in considerable detail, it is not the intention of theapplicants to restrict or in any way limit the scope of the appendedclaims to such detail. Additional advantages and modifications willreadily appear to those skilled in the art, having the benefit of thepresent application. Therefore, the application, in its broader aspects,is not limited to the specific details, illustrative examples shown, orany apparatus referred to. Departures may be made from such details,examples, and apparatuses without departing from the spirit or scope ofthe general inventive concept.

1-13. (canceled)
 14. An apparatus comprising: a solid body of materialhaving a shape, wherein the material includes additive manufacturingpowder, binder material supporting the additive manufacturing powder inthe shape of the solid body, and resin infused within the solid body,wherein the resin is a two-part resin including a resin and a hardener,wherein an inert gas is applied to the two-part resin during mixture ofthe resin and the hardener, wherein the solid body has the configurationof a tool, and wherein the tool is a vacuum mold tool having a formingsurface and air flow channels communicating with the forming surface.15. (canceled)
 16. The apparatus of claim 14, wherein the solid body hasa peripheral surface, and the infused resin penetrates inwardly from theperipheral surface.
 17. The apparatus of claim 16, wherein the solidbody has a thickness between opposed portions of the peripheral surface,and the infused resin penetrates partially through the thickness. 18.The apparatus of claim 16, wherein the solid body has a thicknessbetween opposed portions of the peripheral surface, and the infusedresin penetrates fully through the thickness. 19-20. (canceled)
 21. Theapparatus of claim 14, wherein the vacuum mold tool has trim lines onthe forming surface.
 22. The apparatus of claim 21, wherein the trimlines are defined by cuts in the forming surface.
 23. An apparatuscomprising: a mold tool having a forming surface and air flow channelscommunicating with the forming surface; wherein the mold tool includesadditive manufacturing powder, a binder supporting the additivemanufacturing powder as a solid body having the forming surface, andresin infused within the solid body, wherein the resin is a two-partresin including a resin and a hardener, and wherein an inert gas isapplied to the two-part resin during mixture of the resin and thehardener.
 24. (canceled)
 25. The apparatus of claim 23, wherein thesolid body has a peripheral surface, and the infused resin penetratesinwardly from the peripheral surface.
 26. The apparatus of claim 25,wherein the solid body has a thickness between opposed portions of theperipheral surface, and the infused resin penetrates partially throughthe thickness.
 27. The apparatus of claim 25, wherein the solid body hasa thickness between opposed portions of the peripheral surface, and theinfused resin penetrates fully through the thickness.
 28. The apparatusof claim 23, wherein the mold tool has trim lines on the formingsurface.
 29. The apparatus of claim 28, wherein the trim lines aredefined by cuts in the forming surface.
 30. The apparatus of claim 23,further comprising a base having air flow channels configured tocommunicate with the air flow channels in the mold tool, and railssupporting the mold tool for sliding movement across the base. 31-34.(canceled)
 35. An apparatus comprising: a mold tool having a formingsurface and air flow channels communicating with the forming surface;wherein the mold tool includes additive manufacturing powder, a bindersupporting the additive manufacturing powder as a solid body having theforming surface, and resin infused within the solid body, wherein theresin is a two-part resin including a resin and a hardener, and whereinan inert gas is applied to the two-part resin during mixture of theresin and the hardener; and wherein the mold tool includes an ejectorelement extending through the forming surface.
 36. The apparatus ofclaim 35, wherein the ejector element is flush to the forming surface.37. The apparatus of claim 35, wherein the ejector element includes anair line extending from an underside of the ejector element. 38.(canceled)
 39. The apparatus of claim 35, wherein the ejector elementfurther comprises a poppet.
 40. The apparatus of claim 39, wherein thepoppet can move between a retracted position and an extended position.41. The apparatus of claim 40, wherein the ejector element receives aflow of pressurized air, the pressurized air moves the poppet to anextended position, and the pressurized air flows through the ejectorelement.
 42. The apparatus of claim 41, wherein a vacuum formed materialis oriented in contact with the forming surface, and wherein the poppetapplies force to the vacuum formed material when the poppet is in theextended position.